Moving toward Arrival-Departure GDP

Bill Hall

December 1999

#* Bill Hall 12/16/992

Why Arrival-Departure GDP?

• Arrivals are only half the story

• Rationing departure resources would– Provide control over departure delays

– Improve enroute and arrival predictions

– Allow airlines to determine their own tradeoff between delay and cancellation

• Departure queue control– Reduced fuel use

– Fewer airframe hours

– Less environmental impact

#* Bill Hall 12/16/993

Careful!

• Time constants much faster on departures

• Substitutions must be nearly instantaneous

• Europe rations arrivals and departures all the time– This is not the whole answer

• The real motivation --

– Control over arrival - departure interactions

#* Bill Hall 12/16/994

Airport Capacity

• Interactions between many factors determine airport capacity– Airport configuration

– Mixture of arrivals and departures

– Types of aircraft

• To first order, capacity can be represented in arrival-departure space

#* Bill Hall 12/16/995

The Draper Approach

• Use arrival-departure interactions to everyone’s advantage

• Give users more control

• Require few people in the loop for fast reaction times

• Quantified benefits (from my thesis, May 1999)

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ADCAM

Current Ops

#* Bill Hall 12/16/996

Arrival-departure tradeoff occurs only at a few small airports like BOS and LGA, right?

• For a given configuration, maybe• But make configuration decisions in concert with

demand...

#* Bill Hall 12/16/997

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ORD arrival-departure tradeoff, all configurations

#* Bill Hall 12/16/998

How ADCAM Achieves Benefit

• During GDPs the FAA currently rations arrival capacity only

• This approach ignores the dynamics of arrival-departure interactions

ADCAM uses a better airport capacity model that includes arrival-departure interactions

ADCAM affords the airlines more controlAllows planned operations outside of the box

#* Bill Hall 12/16/999

Current GDP

#* Bill Hall 12/16/9910

ADCAM GDP

#* Bill Hall 12/16/9911

Allocation to Multiple Users

#* Bill Hall 12/16/9912

Allocation Is Dynamic

planned operations -- all airlines

planned United operations

planned Northwest operations

United subcapacity

Northwest subcapacity

other colors -- other airlines

#* Bill Hall 12/16/9913

Outline of Arrival-Departure Capacity Allocation

• ATCSCC makes arrival-departure capacity forecast

• Arrival-departure capacity rationed by schedule (ADRBS)

• Users employ capacity for arrivals and departures as they see fit

• Arrival-departure compression run

#* Bill Hall 12/16/9914

Progress

• We’ve worked out the details of ADCAM implementation

• We’ve implemented Arrival-Departure Ration By Schedule (ADRBS) in software

• We’ve tested the idea in simulation on optimization-based airline models

• We’ve developed visualizations

#* Bill Hall 12/16/9915

Implications for your Airline

• Control delay / cancellation tradeoff for your own operations– You own departure resource, use it how you like

• Get extra arrival capacity when you need it– Preserve bank connection structure

• Get extra departure capacity when you need it– Ramp / gate congestion

• Freedom to hedge against forecast uncertainty

cancellations

depa

rt d

elay

#* Bill Hall 12/16/9916

Implementation Strategy

• Build support infrastructure– Incremental benefit along critical path to ADCAM

– Additional improvements as time and funding permit

• Implement Prototype ADCAM– Start with a demonstration airport

• Needs enough traffic to show benefit

– Pre-operational testing followed by prototype operations

• Extend to entire system

#* Bill Hall 12/16/9917

Path to ADCAM

DepartureDemandPredictor

CDMData Demand

Forecast

CapacityForecast

Capacity-BasedDemand Prediction

Arrival-DepartureCapacity Modeling

TrafficManagers,ATCSCC

ConfigurationPlanning Tool

Arrival-DepartureOp’s Visualization

AirportPlanningPersonnel

GDP What-ifCalculator

ADCAM

AirlineOperationsCenters

critical path development begun useful tools

#* Bill Hall 12/16/9918

What Draper can provide

• ADCAM and simulation tools to analyze ADCAM performance at specific airports

• Prototype Arrival-Departure GDP tools

• Prototype tools for airline decision support under ADCAM

• Support for Prototype Arrival-Departure Operations

• Support for transition to system-wide operations

• Experience analyzing and building real-time systems

• Analytical understanding of ATM and ATFM

• Development to date has been on internal Draper funds

– We’ve invested up the learning curve

#* Bill Hall 12/16/9919

Conclusions

• Arrival capacity depends on departures

• Rationing both gives airlines more control– Significant flexibility available in the airport “physics” not

currently given to the airlines

• Allows better match of demand to capacity– Possible to reduce airborne holding and ground delays

• Allows better match of ATM strategy to demand– Better demand information for configuration planning

– Better tactical flow management (MIT, MINIT, vectoring)

– Better en route modeling and allocation

#* Bill Hall 12/16/9920

Draper is ready

• We could start pre-operational testing within a year of authority to proceed

• We have worked out many of the difficult implementation issues

• We’ve developed supporting software

• We’re excited about this and want to be part of CDM

• Involve us to leverage our findings, our progress to date, and our investment